1. Field of the Invention
This invention relates to a portable device for driving U-shaped anchors into the ground in order to hold in place various types of sheet-like material.
2. Description of the Prior Art
Nurseries for many years have planted grass seed over relatively large areas in order to provide a source of sod. Recently, however, it has become quite common to plant grass seed along highways where the terrain not only slopes but where the profile is irregular. The seedling grass usually requires a considerable amount of care, care that usually makes use of a protective covering. The protective covering most used is what is best termed a blanket or mat comprised of netting and underlying excelsior, the blankets being supplied in the form of rolls that are placed over the newly seeded grass areas, or, in some cases where grass seedlings have already sprouted.
In order to hold the netting and underlying excelsior in place, U-shaped anchors have been manually driven into the ground with a conventional hammer or mallet. Obviously, where large areas are to be covered with such a blanket, the manual process becomes quite tedious and time consuming, as well as costly because of the large amount of labor that is required.
As far as I am aware, no machine has been devised for inserting U-shaped anchors into the ground in order to maintain the netting and excelsior blankets in place. However, straight rigid rods, while not U-shaped, have been used as anchors, and a machine for doing this automatically is described in U.S. Pat. No. 4,410,050, granted Oct. 18, 1983 to Councell, Jr. et al. for "Machine for Inserting Rigid Members in the Soil." This machine is especially designed to drive straight tubes in the ground, doing so intermittently and at spaced locations. However, the use of straight tubes is not as effective as U-shaped anchors in holding the netting and the underlying excelsior in place. Furthermore, the machine disclosed in the alluded to patent is quite complex, massive and costly. While satisfactory for use in a nursery operation, it is not readily transported from location to location, such as needed when anchoring blankets of netting and excelsior along highways.
Consequently, there remains a very real need for apparatus that will effectively and efficiently anchor blankets or mats composed of netting and excelsior to the ground in order to induce the growth of grass.